Multidisciplinary approaches are central aspects of all of our experiments. We routinely use anaerobic microbiology, microbial genomics, molecular genetics, glycobiology and other approaches to better understand the physiology of human gut microorganisms and their viruses.

Below is a list of people in the lab and their current research interests. We have generated a number of experimental protocols and other resources for the research community. Please visit the strains and protocol page to find out more.

Principal Investigator:

Eric C. Martens, PhD

Dr. Martens received his PhD in 2005 from the University of Wisconsin-Madison, working with Heidi Goodrich-Blair, PhD on the biology of the entomopathogenic nematode, Steinernema carpocapsae, and its bacterial symbiont, Xenorhabdus nematophila. He then trained with Jeffrey I. Gordon, MD at Washington University School of Medicine, investigating the physiology of beneficial human gut bacteria, especially members of the Bacteroidetes and their interactions with complex carbohydrates. His current research interests include investigating the roles of gut bacteria in human digestive physiology, the gut microbiome in inflammatory bowel disease and colorectal cancer, genetic exchange between environmental and gut bacteria and mechanism through which gut bacteria break down dietary fiber polysaccharides and mucin glycoproteins.

Postdoctoral Researchers and Fellows:

Ana S. Luis, PhD

Dr. Luis received her PhD in 2017 working with Dr. Harry Gilbert at Newcastle University. Her doctoral research was focused on the enzymatic mechanisms through which commensal gut Bacteroides digest pectins and other dietary fiber polysaccharides, including some of the most complex polysaccharides in our diet rhamnogalacturonans I and II. Her current research is focused on the enzymatic mechanisms by which Bacteroides break down mucin O-linked glycans, a very complex repertoire of glycosylations that are attached to secreted mucus. Bacterial digestion of mucus is a contributor to diet-induced pathogen susceptibility and spontaneous inflammation models being studied in the lab. Dr. Luis is currently funded by a prestigious Marie Skłodowska-Curie Fellowship.

Matthew Ostrowski, PhD

Dr. Ostrowski earned his PhD in 2017 from Stanford University in the lab of Dr. Chaitan Khosla. His research projects in the Martens Lab are focused on bacterial degradation of the food additive polysaccharide, xanthan gum, and the proteolytic mechanisms through which gut bacteria degrade intestinal mucus glycoproteins.

Gabriel Vasconcelos Pereira, PhD

Dr. Vasconcelos Pereira received his PhD in July 2018 working with Dr. Isaac Cann at the University of Illinois, Urbana-Champaign. His research interests in the Martens Lab are focused on the timing and biochemical composition of dietary fibers that restore beneficial gut bacteria and suppress the activity of mucus-degrading bacteria.

PhD Students:

Robert Glowacki, BS

Rob earned his undergraduate degree from Hiram College. His projects in the Martens Lab are focused on the mechanisms through which gut Bacteroides acquire the sugar ribose from various biological sources (nucleosides, RNA) and the effects of this metabolism on bacterial fitness and competition in the gut. Rob is also interested in global gene regulation in B. thetaiotaomicron and its mechanisms for degrading and utilizing mucus glycans.

Mathis Wolter, MS

Mathis is a visiting graduate student from the Luxembourg Institute of Health and is working in the lab of Dr. Mahesh Desai. Mathis is visiting the lab in the Fall 2018 on a Fullbright Scholarship and is studying the contributions of individual mucus-degrading bacteria to Citrobacter rodentium pathogen susceptibility and spontaneous inflammation development in IL-10 knockout mice.

Lab Manager and Technicians:

Nicholas Pudlo, MS

Nick is the lab's manager and also carries several research projects. His main project involves researching the mechanisms through which B. thetaiotaomicron and other Bacteroides exert catabolite repression on the various diet and host polysaccharides they encounter in the gut.

Shaleni Singh, BS

Shaleni joined the laboratory in September 2018 and is working on diet-induced responses by the microbiota, suppression of mucin-degrading bacteria and immunological and mucosal changes during diet-induced IBD development.

Former Lab Members:

Nathan T. Porter, PhD

Dr. Porter received his PhD from the lab in Fall 2017. He used molecular genetic approaches to study how one prominent human intestinal bacterium, Bacteroides thetaiotaomicron, interacts with its host and adapts to the ever-changing environment of the intestine. Particularly, he investigated bacterial polysaccharide capsule biosynthesis and the ways in which production of variable surface capsules mediates interactions with the host immune system and bacteriophage. Nathan is currently doing postdoctoral research with Dr. Johan Larsbrink at Chalmers University if Gothenburg, Sweden.

Mahesh Desai, PhD

Dr. Desai is currently a tenure-track investigator at the Luxembourg Institute of Health.

Elizabeth Cameron, PhD

Dr. Cameron earned her PhD in 2014 and is currently doing postdoctoral research at UT-Southwest and University of Minnesota.

Yao Xiao, PhD

Dr. Xiao is currently working at Thermo Fisher

Theresa Rogers, PhD

Dr. Rogers is currently an Assistant Professor at California Lutheran University

Karthik Urs, MS

Karthik is currently pursuing his PhD research at the University of Texas-Dallas